
What is ash dieback?
It's a disease that affects the UK’s native ash species, the European ash.
Ash dieback is caused by a fungus called Hymenoscyphus fraxineus, which typically enters through the leaves before spreading throughout the tree, eventually strangling its water transport system and causing it to die. H.fraxineus spores spread on the wind, travelling distances up to 16km (10 miles).
Ash dieback, which originated in Asia, was first spotted in nurseries in eastern regions of the UK in 2012. Since then, it has spread westwards and is now found throughout the British Isles. There is no cure for the disease, and experts predict that it has the potential to obliterate up to 90 per cent of the UK’s 150 million mature ash trees, threaten dozens of species that rely exclusively on ash, and cost the economy an estimated £15bn.
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Asked by: Ella Bradbury, via email
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Authors
Ceri Perkins is a New York City-based writer and editor who covers the environment, science, nature and human behaviour. As a freelancer, she has lived around the world, from Madrid to the Scottish Highlands. Before going freelance, Ceri was based in Geneva, Switzerland, as a staff writer/editor at CERN, home of the Large Hadron Collider. Later, she was News Editor at NYC-based magazine Spectrum, where she edited news and opinion stories about the neuroscience and genetic underpinnings of autism. In her spare time, Ceri is typically either outdoors in nature or curled up inside with a stack of books and a pile of things to make or fix. She holds a Bachelor’s in Atmospheric Science, a Master's in Science Communication, and you can read her work in TED Ideas, BBC Earth, The Guardian, Physics World, New Scientist, and more.
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